为完成极化合成孔径雷达(Pol SAR)图像中点散射像素目标的检测,从几何扰动滤波检测点散射像素的基本原理出发,分析了经典方法存在的相干度参数阈值无法自适应获取和不同散射机制共享同一阈值两个问题,提出利用Cloude-Pottier分解结果中...为完成极化合成孔径雷达(Pol SAR)图像中点散射像素目标的检测,从几何扰动滤波检测点散射像素的基本原理出发,分析了经典方法存在的相干度参数阈值无法自适应获取和不同散射机制共享同一阈值两个问题,提出利用Cloude-Pottier分解结果中熵参数的分布情况计算得到阈值,利用平均阿尔法角参数完成不同散射机制的初分类,对初分类的结果排序得到的某种散射机制对应的相干度参数的比例因子,根据比例因子计算得到该类散射机制的阈值,从而完成点散射目标的检测。对机载合成孔径雷达(AIRSAR)数据集中的San Francisco Bay图像进行了实验,结果表明,改进方法在检测性能上优于经典方法。展开更多
The heat capacities C_p and excess heat capaciries C_p^E of four binarysystems cyclohexanone-benzene, cyclohexanone-toluene, cyclohexanone-elhylbenzene,cyclohexanone-isopropylbenzene are measured at 298.15K and under ...The heat capacities C_p and excess heat capaciries C_p^E of four binarysystems cyclohexanone-benzene, cyclohexanone-toluene, cyclohexanone-elhylbenzene,cyclohexanone-isopropylbenzene are measured at 298.15K and under latm by the Calvet microcalorimeter.The error of mole fraction is ±0.0002, of C_p±0.0085, of C_p^E±0.055,arld of temperature ±0.01K. The C_p^E values of the four systems are always positive forwhole ranges of mole fractions. The excess heat capacities decrease with the increase ofnumber of carbon atoms of aromatic hydrocarbon. The experimental results are at variance with the Prigogine-Flory corresponding state theory. The effect of changes of solutionorientational order on C_p^E is also investigated. The intermolecular orientational order entropy parameter θ2S12 is introduced to the Flory model. The Flory model including θ2S12is improved for the estimation of _p^E values.展开更多
Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were m...Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules. Keywords sodium chloride - monosaccharide - enthalpy interaction parameter - entropy interaction parameter - calorimetry展开更多
文摘为完成极化合成孔径雷达(Pol SAR)图像中点散射像素目标的检测,从几何扰动滤波检测点散射像素的基本原理出发,分析了经典方法存在的相干度参数阈值无法自适应获取和不同散射机制共享同一阈值两个问题,提出利用Cloude-Pottier分解结果中熵参数的分布情况计算得到阈值,利用平均阿尔法角参数完成不同散射机制的初分类,对初分类的结果排序得到的某种散射机制对应的相干度参数的比例因子,根据比例因子计算得到该类散射机制的阈值,从而完成点散射目标的检测。对机载合成孔径雷达(AIRSAR)数据集中的San Francisco Bay图像进行了实验,结果表明,改进方法在检测性能上优于经典方法。
文摘The heat capacities C_p and excess heat capaciries C_p^E of four binarysystems cyclohexanone-benzene, cyclohexanone-toluene, cyclohexanone-elhylbenzene,cyclohexanone-isopropylbenzene are measured at 298.15K and under latm by the Calvet microcalorimeter.The error of mole fraction is ±0.0002, of C_p±0.0085, of C_p^E±0.055,arld of temperature ±0.01K. The C_p^E values of the four systems are always positive forwhole ranges of mole fractions. The excess heat capacities decrease with the increase ofnumber of carbon atoms of aromatic hydrocarbon. The experimental results are at variance with the Prigogine-Flory corresponding state theory. The effect of changes of solutionorientational order on C_p^E is also investigated. The intermolecular orientational order entropy parameter θ2S12 is introduced to the Flory model. The Flory model including θ2S12is improved for the estimation of _p^E values.
基金This work was supported by the Outstanding Youth Science Foundation of Henan Province(Grant No.0112000500)the Innovator Foundation for Colleges and Universities of Henan Province.
文摘Dilution enthalpies of sodium chloride and some monosaccharides (glucose, galactose, xylose, arabinose, and fructose) in water and mixing enthalpies of aqueous sodium chloride and these monosaccharide solutions were measured by using an improved precision semimicro-titration calorimeter. Transfer enthalpies of sodium chloride from water to aqueous saccharide solutions were evaluated as well as enthalpy interaction parameters of sodium chloride with these monosaccharides in water. Combined with Gibbs energy interaction parameters, entropy interaction parameters were also obtained. The results show that interactions of the saccharides with sodium chloride depend on the stereochemistry of saccharide molecules. These interaction parameters can identify stereochemical structure of saccharide molecules. Keywords sodium chloride - monosaccharide - enthalpy interaction parameter - entropy interaction parameter - calorimetry
